Art of buffing



R. P. COOL ART OF BUFFING Filed March 26, 1934 2 Sheets-Sheet l jufiy 3, 1935.

R. P. COOL ART OF BUFFING Filed March 26, 1934 2 Sheets-Sheet 2 INVENTOR Patented July 23, 1935 UNITED STATES.

ART OF BUFFING Robert P. Cool, Clinton, Pa., assignor to Standard Steel Spring Company, a corporation of Pennsylvania Application March 26,

3 Claims.

This invention relates to the art of bufiing and more particularly to the buffing of articles having curved cross-sections wherein the curvature is constructed upontwo or more different radii.

While not limited thereto the present invention will be described in connection with the buffin of automotive bumper bars. r

In connection with the manufacture of modern bumper bars wherein there are curved portions constructed on different radii great difiiculty has been experienced in hunting the same. This is in part due to the fact that in using an ordinary buff-wheel it is impractical to obtain a satisfactory and uniform buff thereon because the buffing surfaces cannot be so designed as to buff the entire bar surface in one operation, and in part due to the fact that the industry has always carried out the bufing operations either as one operation or as manipulations in connection with the same buffing wheel. As a result, much twisting and turning of the bumper against the prior buffs has been necessitated and a non-uniform and relatively unsatisfactory buffing operation has been effected. There is a further factor involved in that when it is attempted to buff the edges of bumper bars, this can only be done with comparatively great danger of injury to the workmen as is well known in the industry.

One of the objects of the present invention is to carry out the'buffing operation in two stages upon two different bufiing wheels while at the same time speeding up production.

Another object is to buff simultaneously those curved portions of an article which have a common radius and thereafter to separately buff the remaining portion of different radius, assuming that the article is constructed on only two radii.

A further object is to buff simultaneously the edge portions of a bumper bar on a specially constructed buffing wheel so that the central portion of the bumper bar is left unbuffed and thereafter bufiing the central portion separately.

A still further object resides in the provision of the special buiiing wheels and in those de tails of construction and operation which will be apparent orpointed out hereinafter.

In the accompanying drawings:-

. Figure 1 represents a side elevation of the first stage buffing wheel and bumper bar being buffed thereby; Fig. 2 isan end view of Fig. 1 showing the bumper bar in'section;

Fig. 3 is a plan view of a portion of the bumper bar after the edge portions only have been buffed;

1934, Serial No. 717,452

Fig. 4 is a view similar to Fig. 1 of the second stage bumng wheel and bumper bar;

Fig. 5 is an end view of Fig. i showing the bumper bar in section; and s Fig. 6 represents a fully buffed bumper bar surface.

Similar numerals represent corresponding parts in the various views. v

' Referring first to Figs. 1, 2 and 3, it will be seen that the buffing wheel used in the first stage of the buffing operations consists of; a shaft is which may have a reduced end portion it the extremity of which is threaded at it for the reception of a washer l3 and nut [4. On the reduced portion of the shaft are arranged in spaced relationship two assemblies l5 of buffing elements H5. Each assembly is shown as being composed of seven buffing elements each of one of which may be of the nature apparent from Fig. 1 and may consist of any known or preferred type of bufiing element although, of course, a different number may be used and I am not, of course, limited to the use of any particular number of buffing elements in each assembly it. These assemblies l5 are spaced apart on the shaft by means of a spacing instrumentality ll. This spacing instrumentality may be any desired spacing element, but I have found that a very convenient instrumentality is an assembly of worn down buffing elements. I may, however, use any kind of spacer whether itbe made of wood, steeLcloth, paper, etc. It is clear that if so desired I may omit the spacing instrumentality entirely and may just use suitable collars to maintain the bufling assemblies 5 in suitable position on the shaft and in suitable condition with respect to the compactness thereof. In the conventional way collars it are used to maintain the whole bufling wheel in proper position and condition. Such may be suitably secured in place as by set screws, etc.

Whereas ordinary bufiing wheels are dressed to a more or less true cylindrical surface or may be raked as it is known in the industry to a desired contour, e. g., concave or convex, I so bevel the buffing periphery of each spaced assembly of bufiing elements that the angle of bevel together with the distance apart the assemblies are spaced make precisely the right combination for the particular article being buffed. Accordingly, it is apparent that by means ofthe special edge buffing wheel just described I may readily and quickly buff the marginal or edge portions of various articles. Where this article is a bumper bar the bar is frequently made with the marginal or edge portions constructed on a radius of one half inch and the central portion constructed on a radius of four inches. These figures are merely for the sake of example and the present invention applies not only to bumpers of the specified or other forms and dimensions but to all nonfiat articles having a curved cross-section which is constructed on two or more different radii.

Thus I am enabled to buff simultaneously the (two) portions of the bumper bar or article which are constructed on the same or on a common radius. From a study of Fig. 2 particularly it will be apparent how the angle of bevel of the bufiing assemblies, the spacing therebetween and. the configuration of the particular article being buffed are all interrelated. A bumper bar in position for being buffed is designated by the numeral 59, and has edge portions l9a and central portion [9b. Ordinarily, the buffing of the bumper bar is carried out by inward and outward movement of the pumper with respect to the buffing wheel over suitably arranged rollers, not shown, and which form part of the present invention.

In Fig. 3 a bumper bar or article surface is illustrated after it has been buffed along the marginal or edge portions by means of the edge buffing wheel of Figs. 1 and 2. These buffed edge portions are designated by the numeral 19a and the unbuifed central portion is designated by the numeral |9b,,it hardly being necessary to point out that during the actual bufiing operations a suitable tallow base or other buffing compound is suitably applied to the surfaces being buffed.

The second stage of the buffing operation is carried out by means of the face buffing wheel of Figs. 4 and 5. The general assembly of the buffing wheel is the same as in Figs. 1 and 2 and is more or less conventional, and the buffing wheel itself is made up of a number of buffing elements suitably held in position and then raked to form a concave periphery which is complementary to the curvature of the central portion of the bumper bar or other article being buffed. By subjecting the bumper bar or article in condition shown in Fig. 3 to the bufling wheel of Figs. 4 and, 5, the central portion of the bumper or article is separately buffed, using the same tallo-wbase buffing compound as before, until a brilliant uniformly buffed surface is obtained which is designated as 25 in Fig. 6.

An inspection of Fig. 2 will show that each laminated group of bufiing elements is so configured that it takes the form of the frustum of a cone, lying on its side, and hence termed a lateral cone frustum. The two cone frustums of Fig. 2 are oppositely disposed as will be seen. The bases of both lie away from the center of the buff ing wheel, that is the frustums taper toward each other.

It is thus apparent that instead of attempting to buff the bumper bar or article surface on a single buffing wheel I carry out the buffing in two stages and in each stage bufiing a portion constructed on a different radius, all portions of common radius being simultaneously buffed in one operation. Surprising to say, I find that by carrying out the bufi'mg of bumper bars, for example, as above described, I secure a much improved and more satisfactory surface and at the same time the unexpected result is achieved in that production is actually materially speeded up instead of being out down as might be thought.

In fact, in quantity production due to easier handling and more ready bufiing without any complicated manipulations by the workmen and without any danger of accidents, I have actually produced 40 to 50% more buffed articles in a given length of time than could hitherto be produced by bufiing bars on a single butting wheel by manipulating the bar surfaces against the buffing wheels. Concurrently, there are no seconds or imperfect surfaces and there is no appreciable accident hazard such as is always present when edges of articles are attempted to be buffed according to experience in the industry.

As I have stated the above is intended more in an illustrative than in a limitative manner and I do not deem myself confined thereto other than as limited by the subjoined claims. The number of buifing elements is variable, the spacing is variable, the angle of bevel is variable all depending, of course, upon the article being buffed and its size and curvature. While I prefer to operate the buffing wheels at about 2300 R. P. M. I am not, of course, limited thereto and likewise I may use any suitable buffing compound which I may desire. buffing element itself and may use any desired or preferred type.

I may if I so desire buff only one portion at a time regardless of whether or not the radius of curvature is the same or different than as to any other portion of the article. Although this is possible it is slower, except where the article has only two differently configured portions, and is mentioned for the sake of completeness as being within the scope of the invention.

What I claim as new and desire to secure by Letters Patent is:

l. A buffing wheel comprising a shaft, a p1urality of spaced laminated assemblies of buffing elements thereon,-means to maintain the spacing thereof, means to maintain the assemblies in proper position and condition on the shaft, and a nut on the end of the shaft, said assemblies of lending elements having their buffing surfaces beveled at such an angle that the relationship between the spacing of the assemblies and such angle of buifing surface is proper for the particular article being buffed.

2. A buffing wheel comprising a shaft, a plurality of spaced laminated groups of buffing elements on the shaft, means for maintaining the spacing thereof, means for maintaining the groups of proper compactness, and a nut on the end of the shaft, the buffing edges of the spaced groups of buffing elements being beveled to a predetermined degree depending on the article to be buffed and the spacing of the groups of buffing elements being such that spaced surface portions of the article to be buffed can be buffed without bufiing other surfaces of the article.

7 3. A bufling wheel comp-rising a shaft, a plurality of laminated groups of bumng elements mounted in spaced relation on said shaft, means for maintaining the spacing of such laminated groups, means for maintaining each such group of proper compactness, and a nut on the end of the shaft, the buffing periphery of each such laminated group of bufling elements being beveled and each such beveled group of buffing elements forming a laterally disposed frustum of a cone, adjacent con-frustums being in opposed arrangement,

ROBERT P. COOL. 

